Nakamura, M;
Keys to the Freshwater Fishes of Japan Fully Illustrated
in Colors(2) KENPEI
(1) Ben
Lee (1)
ScotCat
Sources:
Other
Sources:
Relevant
Information:
One of three species of Silurus
that are in Japan and is also the largest. The rock
catfish, S.
lithophilus,
the Biwi catfish, S. biwaensis and the far
eastern catfish S.
asotus.Reproduction:
Based on observations, a female first searches for
a spawning site, with a male following behind. Immediately
the female stops, the male first places his head under
that of the female and then, by bending his body towards
her anal fin, positions himself such that his tail
is towards the end of the female's snout. From this
position, the male then begins to wrap his tail around
the head of the female, gradually winding his body
tighter and moving along the body of the female until
positioned at the center of her body. The male then
winds his body tightly around the dorsal side of the
female's abdomen for 20-30 seconds. The female then
shakes her head from side to side several times, and
orientates her body downward. This behavior causes
the male to become separated from the female. Immediately
after separation, the female releases a large number
of eggs, and circles around with the male following
on the inside. Although gamete release by the male
was not actually observed, it seems likely that the
eggs are fertilised during circling. After circling,
the pair turns round twice violently, causing the
eggs to become widely scattered. The pair then swim
away with the female in the lead.
Common
Name:
Eurasian catfish, Biwi catfish
Synonyms:
Parasilurus biwaensis
Family:
Siluridae
Distribution:
Asia:Endemic to Lake Biwa, Japan. Type
locality: Offshore of Onoé, Lake Biwa-ko,
Japan.
Size:
115.0cm. (3ft 10ins)
Temp:
10-20°C (47-67°F)
p.H.
6.0-8.0.
Reference:
Nakamura, M;
Keys to the Freshwater Fishes of Japan Fully Illustrated
in Colors. Hokuryukan, 1963. Kobayakawa, M., 1989. Systematic
revision of the catfish genus Silurus, with description
of a new species from Thailand and Burma. Jap. J.
Ichthyol. 36(2):155-186. Ferraris, C.J. Jr., 2007. Checklist
of catfishes, recent and fossil (Osteichthyes: Siluriformes),
and catalogue of siluriform primary types. Zootaxa
1418:1-628. Froese, R. and D. Pauly. Editors.
2021. FishBase. World Wide Web electronic publication.
www.fishbase.org, ( 08/2021 ).
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